Switch



Sept. 20, 1932. J. c. BAsHlouM SWITCH Filed Jan. 22, 1931 Fis. Z

dmanr Patented Sept. 20, 1932 UNITED STATES PATENT OFFICE JACOB BASHIOUH, F ERIE, PENNSYLVANIA, ABSIGNOB T0 UNIFLOW ILNUFAC- TURING COMPANY, 0F ERIE, PENNSYLVANIA, A CORPORATION 0F PENNSYLVANIA Application led January 1931. Serial No. Hum

This invention relates to switches, and more particularly to switches having a snapthrow actuating mechanism.

One of the principal objects of the invens tion is the provision of a switch, having a snap-throw mechanism, which is eicient and effective in operation, simple in construction, inexpensive to manufacture, and which is adapted to impart a quick and positive movem ment to the current controlling elements.

Other 'objects and advantages of the invention will be apparent from the following description, the attached drawing, and the appended claims.

m In the drawing, which discloses a preferred embodiment of the invention- Fig. 1 is a view partly in section, as indicated by the line 1-1 of Fig. 3, of a switch constructed in accordance with this invenzo tion;

Fig. 2 is a fragmentary elevational view of the switch in open circuit position;

Fig. 3 is a sectional view taken on the plane of the line 3 3 of Fig. 1; and

Fig. 4 is a diagrammatic showing ltof a portion of the switch mechanism. 'i

The drawing, in which like characters of reference designate like parts throughout the several views thereof, illustrates a switch 30 such as is adapted to open or close an-electrical circuit after a predetermined movement of an actuating means. The switch,

for example, is adapted to start or stop an electric motor according to changes in pres- :45 sure created by the motor, as by means of a pump, which pressure changes are communicated to and are caused to move the actuating means of the switch.

The switch, which is shown as of the double in pole type, comprises a base to which an upstanding frame portion 11 is attached for support ofthe switch mechanism; a removable cover portion 12 being provided for the enclosure of the switch parts. A supporting 5 block 14, preferably formed of some insulating material, is attached to the frame portion 11 as by screws 14', and carries fixed contacts 15 with which are incorporated binding posts 16 for the attachment of lead wires. block 18, which is referably formed of insulating material, 1s pivotally carried by a stud 19 attached to the frame portion 11. The block 18 has attached to it, as by means of bolts 22, flexible contact lingers 23 which are suitably isolated by insulation and which, in one position of the block 18, are adapted to make electrical connection with the fixed contact members 15; the electrical circuit through the switch being completed by means of exible leads 25, each o which is held by one of the bolts 22 while the oposite end of each lead is connected to a binding post 26 to which suitable wires may be attached.

The actuating means for moving the block 18 to open and close the electrical circuit is provided with an operating device which, in the case of a pressure controlled switch, comprises a diaphragm 30 formed of suitable material such as rubber and which is adapted to flex under changes in pressure to move the actuating mechanism of the switch. The diaphragm 30, which is preferably a circular disk, is shown clamped y means of screws 31 between the base 10 and a member 32. The member 32 comprises a cup-like portion 33 having a communicating passage 34 to a threaded portion 35 to which a suitable pipe connection may be attached to provide communication between the controlling pressure and the diaphragm 30. The base 10 is provided with a depressed portion 38 having a diameter similar to that of the portion 33 of the member 32 so that the diaphragm will be free to flex. Movements of the diaphragm under variation of pressure are communicated to the actuatin mechanism by suitable means such as a diskike member 40 which is positioned within the depression 38 in contact with the diaphragm and is provided with an upstanding stem 41 which projects through an opening 42 in the base 10 and is adapted to contact with a lever 44 of the switch actuating mechanism.

As shown the lever 44 is of substantially L shape. It is preferably an integrally formed casting, and comprises an upstanding long arm 46, and a horizontally extending portion 47 at the outward end of which the lever 44 is pivotally supported as by means of a pin 49 which is carried by upstanding spaced lugs 50 which are preferably formed as an integral part of the base 10. The lever 44 may move pivotally about the pin 49 but is restricted against lateral movement by means of the spaced lugs 50, one of which is provided adjacent each side of the lever portion 47. The upstanding arm 46 of the lever preferably comprises spaced parallel webs which are shown joined at 52 adjacent their outer end to provide a support for a spring carrying stud 53.

An increase in pressure within the area 33 of the member 32 will create a flexing movement upwardly in the diaphragm 3() to move the disk 40 and connecting pin 41 upwardly and to swing the lever 44 clockwise as viewed in Fig. 1. Movement of the lever 44 by the diaphragm is resisted by means of a spring 55 one end of which is supported in a bracket 56 attached, as by means of a screw 57, to the frame portion 11 while the other end of the spring 55 is carried by the stud 53 whose threaded end 58 extends loosely through an opening 59 in the bar 52 and carries a spring tensioning adjustment nut 60 which rests upon the bar 52. Unintentional rotation of the nut 60 is restrained by parallel upstanding lugs 61 spaced apart sufficiently to receive the flats of the nut but not sulicient to permit the nut to turn.

The outward end of the upstanding arm 46 of the lever 44 carries a pin 62 for the pivotal support of an arm 63 which is shown positioned between the upstanding parallel webs comprising the lever portion 46. The free end of the arm 63 has pivotally attached to it at 65 a triangular shaped actuating member 66 which is adapted, after a predetermined movement with the arm 63 to move inde'- pendentlly; of that arm and impart a movement tot e block 18. As shown, the actuating member 66 is provided with a tongue extension 68 which is positioned within a slot 69 at the free end of the arm 63 and, as mentioned, is pivotally connected to the end of the arm at 65. A limited amount of angular movement, as shown in Figs. 1 and 2, is permitted between the arm 63 and the member 66 and is provided by a clearance space between the face 70 of the arm 63 and the coacting face 71 of the member 66. Two other faces, 73 and 74, of the member 66 are angularly related to one another to provide opposed cam faces which are adapted to con-- tact with and alternately en age the movable contact carrying block 18. he cam member 66 is urged toward the block 18 by spring tension and as the ressure on the switch diaphragm changes, t e resulting lever movement causes the block 66 to be moved over the block 18. As the apex of the faces 73 and 7 4 crosses the point of contact with the block the direction of applied force exerted by the tension under which the cam is held to the block is reversed to cause the block 18 to move from the position in which it is held by one face of the cam to a reverse position upon engagement by the opposite face of the cam. Friction free engagement between the cam and block 18 results from provision of a roller member 76 whose axle shaft 77 is fixed in the block 18. The free end of the arm 63 and the member 66 are urged downwardly by means of a spring 80, one end of which is carried by a pin 81 which is shown extending between the webs of the lever portion 46 while the opposite end is carried by a stud 82 whose threaded end 83 carries a spring tensioning adjustment nut 84 which is supported on the arm 63. A suitable clearance space 86 is provided within the arm 63 for free movement of the stud 82, and a curved contacting surface 87 is provided onM the face of the member 63 for rolling contact with the nut 84 sothat the arm 63 may move freely and theV spring 80 may always exert a direct pulL-'on the arm. Means are provided for limiting the downward movement of the actuating member 66 with respect to the roller 76, under urge of the spring 80, and comprise outwardly extending lugs 90 which are provided on the faces 73 and 74 adjacent the face 71 of the member. The operating range of the switch ythat is, the pressures at which the switch contacts open and close, may be regulated by adjustment of the nuts 60 and 84, which control the tension of the springs 55 and 8() respectively.

Clockwise movement of the lever 44, from its position as shown in Fi 1, will cause the actuating member or cam lock 66, which is pivoted on the free end of the arm 63, to be moved to the right and to move upwardly on the roller 76 owing to the camming action of the inclined face 73 on the roller 76. This movement continues against the tension of the spring 80 upon further increase in pressure until the point of engagement of the apex of the inclined faces 73 and 74 with the roller 76 becomes so positioned that the tension of the spring 80 causes the member 66 to move independently with respect to the arm 63 so that the face 74 is brought into contact with the roller 7 6. The camming action of the inclined face 74, which is drawn downwardly under urge of the spring 80, causes the block 18 to move in a counterclockwise direction to thereby break the circuit connection between the contacts 23 and 15. This movement occurs very quickly and causes a snap action by the rapid reversal of the force holding the contacts 23 in closed circuit osition so that the contacts are quickly rawn away to open circuit position. The positioning of the switch parts is such that ressure is maintained on the contact carrying block to hold it in closed circuit osition as the cam block passes through its independent movement to present the opposite cam face for reversal of force on the block and its consequent movement to open circuit position. The relationship between the cam member 66 when moving to the right (as indicated by the arrow a: of Fig. 4) and the cam block 18 is such that a force is directed against the roller of the block tending to rotate the block in a clockwise direction and hold ,the contacts closed. The direction in which this force is applied (as indicated by the arrow a of Fig. 4) changes as the point of engagement of the cam apex with the roller moves, and as the cam ap roaches the position at which it moves in ependently, the direction in which the force is applied approaches the center line b through the axes 19 and 'T7 whereupon theholding force bccomes zero. However, due to the proportioning of the arts, this condition of zero force cannot exist in this switch as the cam member is moved through its independent travel while a clockwise lforce is'maintained on the block. By providing such a cam member a rapid breaking of the contacts is assured and, as the cam block cannot dwell in a position at which zero force exists on the contact block, the contacts are not permitted to reach a position at which chattering or arcing might occur.

With the switch in open circuit position, as viewed in Fig. 2, a decrease in pressure will cause a counter-clockwise movement in the lever arm 44 under urge of t'he spring 55 and will result in upward movement of the cam face 74 with respect to the roller 7 6 until a osition is reached at which the member 66 will be snapped under urge of the spring 80 to bring the cam face 7 3 again into contact with the roller 76 so that the tension of the spring 80 and inclined face 73 will move the block 18 to closed circuit position. Counterclockwise movement of the block 18 is limited by suitable means such as a pin 93 which is fixed to the block 18 and projects through an opening 94 in the frame por ion 11 of larger size than the pin'diametg,

Switches of the general type d fbed are frequently used to control the oper tion of a pressure generating device, such as a water pumping system, in which there is a pulsation as the pressure is built up in the system.V

This pulsation is transmitted to the switch actuating mechanism and tends to cause an unstable condition as the actuating mechanism approaches the position at which the to hold it in closed position until the actuating member 66 moves independently to present a new cam face for movement of the contact carrying block. As the independent movement occurs While the block 18 is under tension there is no dead center osition on which the actuating member can well.

This arrangement of parts provides a construction in which the switch contacts, during the period that the pressure is building up prior to breaking of the contacts t0 open circuit position, are held securely in closed circuit position so that chattering and arcing are prevented. Also, this construction permits a rapid break at the moment of change so that any tendency for the contacts to burn or pit as a result of a. long drawn-out are is eliminated.

While the form of ap aratus herein described constitutes a pre erred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. In a device of the class described, an actuated member, actuating means therefor comprising a movable member, an arm pivotally connected to said movable member, the free end of said arm being arranged closely adjacent said actuated member, and an actuating member pivotally connected to said arm adjacent said free end and positioned to cooperate with said actuated member for movement thereof, said actuating member being adapted to move in a free and urestrained manner independently of said arm, and spring means connected to said arm so as to hold said actuating member in tensioned engasement with said actuated member.

2. In a device of the class described, an actuated member, actuating means therefor comprising a movable member, an arm pivotally connected to said movable member, and an actuating member pivotally connected to said arm and comprising o posed cam faces positioned 'to cooperate with said actuated member for movement thereof, said actuatin g member being adapted to move independently of said arm, and having provisions for limiting its movement relative to said arm.

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3. In a device of the class described, a pivoted actuated member, actuating means therefor comprising a movable member, an arm pivotally connected to said movable member, and an actuating member freely pivoted to a portion of said arm for movement relative to said arm and having an apex point defined by opposed cam faces positioned to cooperate with said actuated member for movement thereof, and spring means for urging said arm portion generally in the direction of a line containing said apex point and the pivoted axis of the actuated member.

4. In a device of the class described, an actuated member, actuatingmeans therefor comprising a movable member, an arm pivotally connected to said movable member, a triangular block having an extension from one side freely pivoted to an end of said arm, said side being arranged adjacent said arm to provide limited pivotal movements of said block, the other two sides of the block being adapted for alternate camming engagement With the actuated member.

5. In a device of the class described, an actuated member, actuating means therefor comprising a movable member, an arm pivotally connected to said movable member, an actuating member pivoted to said arm for free and unrestrained movement between limiting positions relative to said arm and having opposed cam faces positioned to cooperate With said actuated member for movement thereof, and a fixed stop means limiting the movement of said actuated member to an amount coordinated with the limited movement of said actuating member to maintain one or the other of said camiaces in effective camming engagement with said actuated member.

6. In a device of the class described, an actuated member, actuating means therefor comprising a movable member, an` arm pivotally connected to said movable member, and an actuating member pivoted to said arm for free and unrestrained movement between limiting positions relative to said arm and having opposed cam faces positioned to cooperate with said actuated member for movement thereof, said actuating member and said arm having cooperatingr stop faces limiting the pivotal movement of the actuating member on the arm.

7. In a device of the class described, a pivoted actuated member, a contact movable thereby to 'open and closed circuit positions, actuating means therefor comprising an actuating member movable with respect to said actuated member, resilient means operable to tension said actuating member against said actuated member, said actuating member being adapted to be moved from a position in which force is directed against the actuated member with a substantial component in one direction to a position in which the said force component is reversed for movement of the actuated member, the reversalof the direction of said force component occurring while tension is maintained against the actuated member with a substantial force component in the direction of movement of the actuat ing member.

8. In a device of the class described, a pivoted actuated member, a contact movable thereby to open and closed circuit positions, actuating means therefor comprisingr an actuating member movable with respect to said actuated member, carrying means for said actuating member, resilient means operable to tension said actuating member against said actuated member, said actuating member being adapted to be moved from a position in which force is directed against the actuated member with a substantial component in one direction to a position in which the said force component is reversed for movement of the actuated member, and provision for a limited amount of independent movement of said actuating member with respect to said carrying means .for reversal of the direction of said force component while tension is maintained against the actuated member to give a substantial force component in the direction of the movement of the actuating member.

9. In a device of the class described, a pivoted actuated member, a contact movable therebyv to open and closed circuit positions, actuating means therefor comprising an actuating member movable with respect to said actuated member, resilient means for tensioning said actuating member against said actuated member, said actuating member being movable from a position in which the force it directs against the actuated member has a component in one direction to a position in i which the force that it exerts against the actuated member has a component in a reversed direction for movement of the actuated member from closed circuit to open circuit position, and lost motion provision for independent movement of said actuating member with respect to said actuated member at the time of reversal of the direction of said force, so that the direction of said force component is reversed while tension is maintained against the actuated member with a substantial force component holding the actuated member in circuit closed posi tion up to the instant of force component reversal.A

10. In a device of the class described, a pivoted actuated member, a contact movable thereby to open and' closed circuit positions, said actuated member having a curved cam surface, actuating means therefor comprising an actuating member having a pointed end engaging said curved cam surface and movable with respect to said actuated member, carrying means pivotally supporting said actuating member for limited relative movement thereon, resilient means for tensioning said actuating member a ainst saidicam surface, said actuating memger being adapted to be moved from a sition in which the force n that it exerts against the curved cam surface holding it in circuit closed position until relative movement takes place between the actuating member and its carrying means.

11. In a device of the class described, a pivoted actuated member, a movable arm, a pivot support for said arm, a pointed part having opposed cam faces, a roller part cooperating with said pointed part, a pivotal mounting on said arm for one of said parts and supporting said part for swinging movement, the other of said parts being provided on said pvoted actuated member, and spring means connected to said arm for tensioning said arm so as to hold said one part against the other part.

12. In a device of the class described, a pivoted actuated member, an actuating arm, a pivotal support for said arm, a roller part, a pointed part having opposed cam faces adapted for engagement with said roller part, means pivota ly supporting said roller part and said pointed part on said actuated member and said arm, sprin means acting on said arm so as to hold sai roller part and said pointed part in tensioned engagement with one another, the ivotal supports of said roller part and sai pointed part being arranged generally in allgnment with the point of engagement of said pointed and roller parts and with the pivot axis of said actuated member.

13. In a device of the class described, a pivoted actuated member, an actuating arm member, a pivotal support for said arm member, a pointed part provided on said arm member and having opposed roller en aging cam faces, a roller part carried by sai actuated member, spring meansvacting onsaid v arm member so as to hold said roller part and said pointed part in tensioned engagement with one another, and a pivoted lever member supporting one of sald parts for limited swinging movement on one of said members on an axis generally in line with the axis of rotation of the pivoted actuated member and the point of contact of the roller and pointed part.

14. In a device of the class described, a pivoted actuated member, actuating means therefor comprising a movable member, an arm pivotally connected to said movable member. a roller pivotally mounted on said actuating member, an actuating member freely `pivoted to a portion of said arm for free an unrestrained swinging movement relative to said arm and having a pointed end defined by opposed cam faces, spring means for urging said arm generally in the direction of a line containing said ointed end and the pivot axis of the actua member, said arm and actuating member having cooperating stops limiting the swinging movement of said actuating member to a small angle.

In testimony whereof I hereto allix my signature.

l JACOB C. BASHIOUM.

cEnTlrlcArE or comcrlou.

mem No. 1, 87o, 456. september zo, 1932'.

JACOB C. BASHIOUM.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, line 66, claim 14, for "actuating" first occurrence, read actuated; and that the said Letters Patent should be read with this correction therein that the same may conform to the reeordoi the case in the Patent Office.

Signed and sealed this 29th day of November, A. D. 1932.

M. J. Moore, (Seal) Acting Commissioner of Patents. 

